Spark-plug.



- F. I. MATHIAS.

SPARK PLUG.

APPUCATION FILED FEB 28. 19H.

INVENTOR Patented Jan. 8,

AT @HNEY an on SPARK-PLUG.

Application filed February 28, 1917.

To all whom it may concern:

Be it known that I, FRANK J. MATHIAS, a citizen of the United States,residing at Fremont, in the county of Sandusky and State of Ohio haveinvented certain new and useful Improvements in Spark-Plugs, of whichthe following is a specification.

This invention relates to spark plugs.

One of the main objects of the invention is to provide a spark plug foran internal combustion engine in which the spark points or terminalmembers may be adjusted toward or away from each other so as to vary thespark ga p to suit circumstances. A. fur ther object is to provide aspark plug of simple construction which may be produced at VQfy smallcost having a removable cover by means of which access to the interiorof the plug may be had without removing the plug from the enginecylinder. .A further object is to provide a spark plug having aremovable cover provided with a pot-cock by means of which communicationbetween the interior of the plug and the atmosphere may be estabiishedfor cleaning the terminal members in the event of these members becomingfouled. A still further object is to rovide a r ltw so constructed thatcarbon sticks may be used as terminal members thus permitting thesemembers to be quickly and easily renewed at very small cost.

in the drawings Figure 1 is a side view of a spark plug constructed inaccordance with my invention Fig. 2 is a section taken on line 22 ofFig. 3,

Fig. 3 iso. central vertical section through the ping.

The plug made of hardened steel, iron, or other suitable material. isprovided with a cylindricai hollow body 1 and reduced .neck 2 inte raitherewith which is exteriorly threaded as at 2 so as to permit the plugto be readily secured through the wall of an engine cylinder in theusual manner. The upper portion of body 1 is exteriorly threaded toreceive a cover or closure memher 3" threaded thereon, which is providedwith an integral hexagonal flange 4 so as to permit the cover to besecured tightly onto the body. Cover 3 of approximately hemisphericalshape and provided, at its center, with a threaded bore into which isthreaded the stern a pet-cock 5.

The body 3. is provided with a flattened Specification of LettersPatent.

through the flattened portion (3 thus forni- Scrial .ifi'o. 151,548.

portion 6. An opening is provided through this flat portion and receivesan insulating thimble 7 of mica or other suitable insulating material,this thimble being provided at each end with an integral annular flange7 hich projects beyond the periphery of the opening. Thimble? isprovided with a central bore which snugly receives a terminal member supmri'ing rod 8. Rod 8 is pro vided with the tl'ireadcd portions 8 and 8*adjacent each end of thimble 7. A nut 9 is threaded on the rod adjacentthe outer end of the thimble, a similar nut 10 being threaded on-the rodadjacent the inner end of the thiihble. These two nuts coact to compressthe insulating t mble 7 so as to force theysnino into tight engagementwith the body .1 of the ping about the opening ing a fluid tight.closure therewith. The nuts also act tosccure the rod 8 in axialadjustment through the thimble.

Rod 8 is przwitlcil, adjacent its inner end, with a diametrical boreadapted to receive a terminal member 11, this member being a pencil orstick oi carbon. Terminal more ber 11 may be adjusted through the rod(-3 bymeans of a set screw 12 threaded rod and engaging this member. Ablock 13 of any suitable electrical COHliln ing material issecured tothe base of bodv 1 adjacent neck 2. This block is proviz' with avertical bore which recei es the im an end of a carbon stick 14.-corresponding to stick 1 A set screw 15 serves to secure the terminaimember in position.

This plug; is especially adapted for with high tension ignition systems,the termipal member 14-. being electrically connected to one side ofthis system b means of the engine and the base frame in the usua.manner. The terminal member 11 may connected to the other side of theigniti system by means of a connecting nut threaded e. 1e outer end oirod 8 wuic. cooperates i ii an :uinuiar shouidcr H to secure the end ofconduct-or n the rod. In using this plug the out. passing from oneterminal. member to the other will cause a spark igniting: the charge ofexplosive mixture in the cylf. idler in the usual manner. By adjustingthe, r r} 8 through thimble 7 the spark n) may varied as desired. Also,by 21K terminal member 11. through red of the two terniinai commodeted,and the vertical height or Width of the spark gap may be varied so as tovary the intensity of the spark.

In the event of the terminal members 11 and 14 becoming fouled, the petcock 5 may be opened, and the engine operated so as to clean theseterminal members in the usual manner. The cover may be quickly andeasily removed from the body 1 when necessary so as to permit access tothe interior of the plug for adjusting or renewing the terminal members,or for adjusting the rod 8 axially so as to vary iihe Wltlill of thespark gap, and may be as quickly and easily replaced when the desiredadjustment has been. made.

A spark plug constructed in accordance with my invention may be producedat very small cost, and permits quick and easy adjustment of theterminal members, it being possible to obtain access to the interior ofthe plug Without the necessity of removing it from the engine cylinder.ln addition, I am enabled to use terminal members made of carbon whichmay be produced at ery small cost, one of these members being adjustableso as to accommodate wear of the terminals due to arcing between thesame.

l ihat l claim is:-

fl. ln spark plugs, a hollow bot y, a terininal'member carried by saidbody and electrically connected thereto, a terminal member supportingrod secured. r-lirough the "all. of said body and etric-ally insulatedtherefrom, and tc i. .nal' member z'uiljustably mountedrin said adjacentthe inner end thereof and movable toward and array from rninal mcniibercari cal by the hal cl Q. In spark plugs, a hollow body, an upxiardlyextending terminal member carried by said body and electricallyconnected. tliercto',';a terminal member supg'iorting rod secured.through tliewall of said body and electrically insulated therefrom, abar minal member carried by said rod and eX- tending in parallel spacedrelation to the terminal member carried by the body of the casing, theterminal member carried by said rod being axially adjustable whereby theeffective height of the spark gap between the two said terminals may bevaried.

3. ln spark plugs, a hollow cylindrical body, an insulating tliimblemounted through the Wall of said body, terminal member supporting rodmounted through said thimble adjusting nuts threaded on said rod jacenteach end of the thimble, means for securing a terminal member to saidrod at the inner end thereof, a terminal member arried by said bod and aclosure member removably secured on said body.

In spark plugs, a hollow body, a minal member carried by said body andtrically connected thereto, a terminal. member supporting rod adjustablysecured through the Wall of said body and elect-rically insulated fromthe same, a terminal member adjustably secured through Said rod adjacentthe inner end thereof, and a closure member removably secured on saidbody:

l n testimony whoreoi l allix my signature in presence or ewe Witnesses.

l lhil lli J. .l'li ilf'lllhfil. l itnesses:

GIEQ. ZEIGLER, C. ll. CARR.

